1965 was the first year for disc brakes on the Corvette, in fact '65 was the year that most GM vehicles were first offered with discs. The OE Delco Moraine calipers featured 4 pistons with lip seals to keep the brake fluid from leaking out.
When working correctly, these brakes do their job very well, however they are prone to leaks which can significantly (and dangerously) reduce braking performance. Many Corvette owners have had their calipers rebuilt with o-ring seals and stainless steel bores, but this is no guarantee of reliable, long-term performance.
There were 3 different Delco Moraine caliper designs used from 65-82, each having different casting numbers. All 3 caliper designs are interchangeable, so many early cars may now have later calipers fitted. Original, 'First Design' 1965 calipers would have a casting number starting with #546.
First Design: 1965 – 1966 (and some very early '67s)
Front: Left #5465954; Right #5465952 – Rear: Left #5465902; Right #5465905
Second Design: 1967 – 1971 (and some very early '72s)
Front: Left #5452270; Right #5452273 – Rear: Left #5452281; Right #5452284
Third Design: 1972 – 1982 (the most common calipers)
Front: Left #5473795; Right #5473796 – Rear: Left #5473806; Right #5473807
It was common practice to exchange old caliper cores for rebuilt cores. The calipers that were fitted to the Red Rocket (pictured below) were purchased by owner Galen Dae from Carter's Corvette Parts in Livermore CA in 1991, and he handed over the original calipers in exchange. A receipt for this transaction is included in the car's history file.